Probably the biggest piece of digital music news to come out of CES 2008 was that Napster was planning to offer its complete catalog of more than 6 million tracks in the unprotected MP3 format.

On Tuesday, with the launch of version 4.5 of the software and store, that announcement becomes a reality. Although digital music stores such as eMusic, Amazon MP3, and even Napster itself already had MP3s on offer before this point, the collective catalogs of all three didn't even come near the volume of tracks you can find in the entire Napster library. All four major labels and thousands of indies are represented in the store, and every track will be available at the standard 99 cent price point.

In addition, Napster's Web-based store, which is all that is required for MP3 purchases and downloads, is compatible with every operating system. And--of course--the MP3s can be played on any MP3 player, portable video player, or music cell phone. Currently, 95 percent of the catalog is encoded at 256Kbps, which is reasonably high-quality for an MP3, and each track comes with hi-resolution album art (at least 1,000x1,000 pixels). Although Napster has quite an international presence, the MP3 store will only be available to U.S. residents for the time being.

Napster will continue to offer its online and To Go subscription services for $12.95 or $14.95 per month, respectively. The music associated with a subscription will remain in the protected WMA format with the time-out capability.

The company did make some improvements to its online interface. It now features a "liquid layout," which resizes everything within both the store and media player windows when you adjust the size of either window. Napster has also improved its download management system so that users can better view what has been purchased already and whether it was ever downloaded after the purchase.

Sadly, because of label restrictions, Napster will not be offering any type of trade program for customers who have a library of DRM-protected WMA files that they purchased a la carte. However, the licenses on those files will continue to be supported by the service, so no need to worry about a repeat of the MSN Music scandal. At least not for now.